While viewers wonder about Kate Pearson’s relationship with her mother in NBC’s hit show This Is Us, the two actresses’ off-screen relationship is nothing but love.

“I have revered Mandy Moore for so long, and I just love her, and she’s just like a perfect human,” Chrissy Metz, 37, told PEOPLE of her younger costar and on-screen mother.

Metz’s close bond with the 32-year-old caught her off guard at one point on set: the first time she witnessed Moore’s aging makeup in person.

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“The first time I saw her I cried,” the 36-year-old actress revealed of the transformation. “I thought it was somebody else. I thought it was an executive, right? And I was like, ‘Oh, hi… Nice to… Oh, my god!’ And I started crying.”

“I saw this like love in her eyes, and it’s obviously a different person, so it was emotional for me,” Metz continued. “But yeah, it’s awesome, awesome work.”

Sadly, in the latest episode, it was revealed that the pair’s characters aren’t on the best of terms due to mother-daughter issues. But that wasn’t hard for Metz to swallow.

“To be able to potentially play opposite, it was so exciting, even if the dynamic isn’t always perfect, because we know that their relationship has kind of been strained,” Metz said. “But I just knew that it was going to be wonderful.”